This invention relates to disposable tubular devices of the type used with medical instruments for delivering fluid to or evacuating fluid from a patient.
Tubular devices for transporting fluids between a patient and a medical instrument are typically used by medical professionals such as physicians, dentists and dental technicians, and veterinarians for suctioning fluid from or irrigating a part of a patient's body. One such tubular device is a disposable syringe tip for an air-water dental syringe.
A typical syringe tip has a central water passageway and at least one passageway through which air may flow. The tip is typically sealingly retained in a syringe hand-piece by a retaining collar which compresses an O-ring against the tip to seal the connection between the tip and the handpiece. Between uses of the syringe, the tip must be removed from the hand-piece by wholly or partially disengaging the retaining collar. The tip is then either sterilized before reuse or discarded and replaced with a new syringe tip.
A disadvantage encountered with prior syringe tip designs is the difficulty in having a quickly detachable tip which provides a water-tight seal between the central water passageway of the tip and a water conduit of the hand-piece. In some syringes, no elastomeric seal is placed between the water conduit and the central water passageway. In such syringes, water may leak between the conduit and the tip. In other conventional syringes, O-rings are positioned between the end of the tip and the water conduit of the hand-piece. With these syringes, the O-ring is repeatedly used until the O-ring fails, which may be at an inopportune time. Also, unless the O-ring is squeezed between the hand-piece and the tip, the O-ring will not prevent leakage. Further, the force of water from the conduit tends to unseat the tip from the O-ring.